From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=DKIM_ADSP_ALL,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9B713C742A5 for ; Fri, 12 Jul 2019 08:23:04 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id 33FC32064B for ; Fri, 12 Jul 2019 08:23:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=amazon.de header.i=@amazon.de header.b="gyUhg1vs" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 33FC32064B Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=amazon.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvmarm-bounces@lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id C70DA4A53D; Fri, 12 Jul 2019 04:23:02 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@amazon.de Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id tL+8hpVlIKBR; Fri, 12 Jul 2019 04:23:01 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 0478E4A502; Fri, 12 Jul 2019 04:23:01 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 689394A4BE for ; Fri, 12 Jul 2019 04:23:00 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 7S8Lx4HjEiOZ for ; Fri, 12 Jul 2019 04:22:59 -0400 (EDT) Received: from smtp-fw-6001.amazon.com (smtp-fw-6001.amazon.com [52.95.48.154]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 03BBE4A4A9 for ; Fri, 12 Jul 2019 04:22:58 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.de; i=@amazon.de; q=dns/txt; s=amazon201209; t=1562919778; x=1594455778; h=from:to:cc:subject:date:message-id; bh=2GHXvodd5mYiOI7g2dcIp8dLyBwMPtlaooER9mc1rHw=; b=gyUhg1vsaIObtkpZPaaVVpaxpkwOoilN48zS4zmf1/WpGmnvERXfrHGP hbrxp580FhpbN98lvIxaQdW3MpmppEWgpPaxNNiV7ON4TraQzn5J3wL+9 V3yhqCOzqdjbonazKrK4zF9dQmFEWD1OOxtARQnS0Ym4UdCWTetSN6PXM 8=; X-IronPort-AV: E=Sophos;i="5.62,481,1554768000"; d="scan'208";a="404647834" Received: from iad6-co-svc-p1-lb1-vlan3.amazon.com (HELO email-inbound-relay-1a-af6a10df.us-east-1.amazon.com) ([10.124.125.6]) by smtp-border-fw-out-6001.iad6.amazon.com with ESMTP; 12 Jul 2019 08:22:57 +0000 Received: from u54e1ad5160425a4b64ea.ant.amazon.com (iad7-ws-svc-lb50-vlan3.amazon.com [10.0.93.214]) by email-inbound-relay-1a-af6a10df.us-east-1.amazon.com (Postfix) with ESMTPS id 8BFEEA252A; Fri, 12 Jul 2019 08:22:53 +0000 (UTC) Received: from u54e1ad5160425a4b64ea.ant.amazon.com (localhost [127.0.0.1]) by u54e1ad5160425a4b64ea.ant.amazon.com (8.15.2/8.15.2/Debian-3) with ESMTP id x6C8MoPk016257; Fri, 12 Jul 2019 10:22:50 +0200 Received: (from karahmed@localhost) by u54e1ad5160425a4b64ea.ant.amazon.com (8.15.2/8.15.2/Submit) id x6C8MnRH016242; Fri, 12 Jul 2019 10:22:49 +0200 From: KarimAllah Ahmed To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH] KVM: arm/arm64: Properly check for MMIO regions Date: Fri, 12 Jul 2019 10:22:08 +0200 Message-Id: <1562919728-642-1-git-send-email-karahmed@amazon.de> X-Mailer: git-send-email 2.7.4 Cc: KarimAllah Ahmed , Marc Zyngier , kvmarm@lists.cs.columbia.edu X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu Valid RAM can live outside kernel control (e.g. using "mem=" command-line parameter). This memory can still be used as valid guest memory for KVM. So ensure that we validate that this memory is definitely not "RAM" before assuming that it is an MMIO region. One way to use memory outside kernel control is: 1- Pass 'mem=' in the kernel command-line to limit the amount of memory managed by the kernel. 2- Map this physical memory you want to give to the guest with: mmap("/dev/mem", physical_address_offset, ..) 3- Use the user-space virtual address as the "userspace_addr" field in KVM_SET_USER_MEMORY_REGION ioctl. One of the limitations of the current /dev/mem for ARM is that it would map this memory as uncached without this patch: https://lkml.org/lkml/2019/7/11/684 This work is similar to the work done on x86 here: https://lkml.org/lkml/2019/1/31/933 Cc: Marc Zyngier Cc: James Morse Cc: Julien Thierry Cc: Suzuki K Pouloze Cc: linux-arm-kernel@lists.infradead.org Cc: kvmarm@lists.cs.columbia.edu Cc: linux-kernel@vger.kernel.org Signed-off-by: KarimAllah Ahmed --- virt/kvm/arm/mmu.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index 06180c9..2105134 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include #include @@ -89,7 +90,7 @@ static void kvm_flush_dcache_pud(struct kvm *kvm, static bool kvm_is_device_pfn(unsigned long pfn) { - return !pfn_valid(pfn); + return !memblock_is_memory(__pfn_to_phys(pfn)); } /** @@ -949,6 +950,7 @@ static void stage2_unmap_memslot(struct kvm *kvm, do { struct vm_area_struct *vma = find_vma(current->mm, hva); hva_t vm_start, vm_end; + gpa_t gpa; if (!vma || vma->vm_start >= reg_end) break; @@ -959,11 +961,14 @@ static void stage2_unmap_memslot(struct kvm *kvm, vm_start = max(hva, vma->vm_start); vm_end = min(reg_end, vma->vm_end); - if (!(vma->vm_flags & VM_PFNMAP)) { - gpa_t gpa = addr + (vm_start - memslot->userspace_addr); - unmap_stage2_range(kvm, gpa, vm_end - vm_start); - } hva = vm_end; + + if ((vma->vm_flags & VM_PFNMAP) && + !memblock_is_memory(__pfn_to_phys(vma->vm_pgoff))) + continue; + + gpa = addr + (vm_start - memslot->userspace_addr); + unmap_stage2_range(kvm, gpa, vm_end - vm_start); } while (hva < reg_end); } @@ -2329,7 +2334,8 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm, vm_start = max(hva, vma->vm_start); vm_end = min(reg_end, vma->vm_end); - if (vma->vm_flags & VM_PFNMAP) { + if ((vma->vm_flags & VM_PFNMAP) && + !memblock_is_memory(__pfn_to_phys(vma->vm_pgoff))) { gpa_t gpa = mem->guest_phys_addr + (vm_start - mem->userspace_addr); phys_addr_t pa; -- 2.7.4 _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm